1. Field of the Invention
The present invention relates to a zoom lens and an imaging apparatus, and particularly to a zoom lens appropriate for a video camera, a camera for broadcasting, a surveillance camera and the like, and an imaging apparatus including the zoom lens.
2. Description of the Related Art
Conventionally, as a zoom lens usable in the aforementioned fields, a four-group lens system, in which a positive first lens group, a negative second lens group, a positive third lens group and a positive fourth lens group are arranged in this order from an object side, is known. For example, Japanese Unexamined Patent Publication No. 2006-047771 (Patent Document 1), U.S. Pat. No. 7,227,699 (Patent Document 2) and Japanese Unexamined Patent Publication No. 2007-127694 (Patent Document 3) disclose a four-group zoom lens, in which a first lens group and a third lens group are fixed and a second lens group and a fourth lens group move when the magnification of the zoom lens is changed from wide angle end to telephoto end. The four-group zoom lens is a rear-focus type lens system, in which focusing is performed by the fourth lens group. The lens systems disclosed in Patent Documents 1 through 3 are structured so that a blur in an image to be imaged is corrected by moving a part of an optical system in the third lens group in such a manner to have a component perpendicular to an optical axis.